Last Modified: Feb 13, 2019
See more info
Known Affected Versions:
11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9
11.6.0, 11.5.2, 11.4.1 HF9
Opened: Apr 30, 2014
Related AskF5 Article: K16026
If there are multiple set cookie rewrites to an HTTP response header, then there is a chance that tmm might core due to referencing incorrect locations into the buffer. TMM may crash and leave an error message in one of the TMM log files (/var/log/tmm*) similar to: notice 2: lib/c/xbuf.c:930: xbuf_subtract: Assertion `valid xfrag subtraction' failed.
Traffic disrupted while tmm restarts.
The original issue occurred with ASM, but is not specific to ASM. It can occur whenever the rewrite profile is used and the the path/domain within the set cookie filed of an HTTP response header is rewritten.
This issue has no workaround at this time.
If there are multiple set cookie rewrites to an HTTP response header, tmm no longer cores due to referencing incorrect locations into the buffer.